1. Field of the Invention
The present invention relates to an image blur correction apparatus, and more particularly to an image blur correction apparatus that corrects (prevents) image blurs caused by vibration of a camera or the like.
2. Description of the Related Art
A device is known which is configured to correct image blurs as an image blur correction apparatus for a television camera. In this device a vibration proof lens is disposed in an imaging optical system in a condition whereby it can move freely in a plane perpendicular to the optical axis. When a vibration is applied to the camera (camera's imaging optical system) the vibration proof lens is driven by an actuator so as to cancel out an image blur produced by that vibration (for example, see Japanese Patent Application Laid-Open Nos. 2001-142103 and 2003-107554). Other methods are also known which correct an image blur in addition to the above method using a vibration proof lens that moves in a plane perpendicular to the optical axis. A correction amount (corresponding to a displacement amount of the vibration proof lens when using a vibration proof lens) for canceling out an image blur with respect to a vibration applied to a camera can be determined, for example, by detecting the vibration applied to the camera using a blur detection sensor such as an angular velocity sensor, and calculating the correction amount based on the blur signal output from the blur detection sensor.
A camera (optical system) has already being proposed that refers to a blur signal obtained from a blur detection sensor to automatically determine whether or not an intentional operation (pan/tilt operation) is being performed to change the imaging composition that is not a vibration, such as a panning operation or tilting operation, and when the camera determines that a pan/tilt operation is underway it switches the image blur correction mode to a mode suited to performing a pan/tilt operation. For example, a camera has been proposed which, upon determining that a pan/tilt operation is underway, halts image blur correction (or reduces the effect of image blur correction) in order to eliminate poor operability with respect to a pan/tilt operation or unnaturalness of an image caused by image blur correction being performed at the time of the pan/tilt operation (for example, see Japanese Patent Application Laid-Open No. 2002-229089). A determination (pan/tilt determination) as to whether or not a camera is performing a pan/tilt operation is, for example, made by detecting whether or not the size of a blur signal from a blur detection sensor continuously exceeded a predetermined threshold value for a given time or more.